The ghost that is freed if you pull the sword in the stone? That's not a glitch, he kills everyone if you don't put the sword back.
Mhm, isn't that a bit too harsh? If you don't have an extra game saved you're pretty much screwed lol.
No, that's another lesson - always have a backup save. Always.
The Sword In The Stone, however, teaches you a lesson of ... greed, for example.
I'm sorry, but how is this a lesson of greed? Sword does not belongs to anyone, there is no greed factor plays the role if you pick it up (just like if you pick up anything from the ground). Nonsense.
But if you did steal it from some family that being protected by family spirit...